Firefox 22 implements technology called WebRTC, an open-source project backed by Google, Mozilla and Opera that allows real-time communication between Web applications without extra plugins or software like Adobe Flash.

Mozilla technical evangelist Robert Nyman in a blog post said that while earlier versions of Firefox supported an API component of WebRTC, getUserMedia (gUM), through which Web apps could access microphones and video cameras, this is the first time Mozilla has made WebRTC available in a stable release.

"We believe the industry has only scratched the surface of what's possible with WebRTC, and only by getting it into the hands of developers and early adopters will we see this technology's true potential," said Nyman.

Google already supports WebRTC in Chrome. While Apple does not support it in either current or announced versions of iOS or OS X -- possibly because WebRTC could pose competition to the company's FaceTime messaging system -- Google is reportedly working on an SDK to implement WebRTC in iOS.

Microsoft also does not support WebRTC in Internet Explorer. It prefers a similar technology called CU-RTC-Webc. One major objection that Microsoft and Apple appear to have with WebRTC is that it relies on the royalty-free VP8 video codec rather than their H.264 codec.

Presently, Web developers can use TokBox's OpenTok platform to write WebRTC applications that work in browsers from Apple, Google, Microsoft and Mozilla.

Firefox 22 also includes support for asm.js in its OdinMonkey JavaScript engine. Asm.js is a subset of JavaScript produced by running C/C++ code through Mozilla's Emscripten compiler. The resulting code runs fast enough in the browser that it offers users of graphics-intensive applications like 3-D video games an experience that's nearly as good as apps written in native code. That's a huge win for Web apps, which have traditionally been much slower than native apps for high-performance tasks.

"Mozilla is pushing the boundaries for what is possible on the Web today and proving the Web is the best development platform with advancements like these that improve interoperability and end fragmentation," the company said in a blog post.

In addition, Firefox 22 brings several other improvements: On Windows, it obeys display scaling options when enlarging text on high-res displays; on OS X, it displays the progress of downloads in the Dock application icon; the playback rate of HTML5 audio and video can now be changed; and the Add-Ons Manager now supports management of online social services.

The mobile version of Firefox 22 for Android has also been updated, though it has fewer changes worthy of note.